Virtual Lab: Atomic Emission Spectra General Information and Questions: 1. What happens when a sample of an element is excited by a high-energy electric discharge or heat? 2. What happens to the light given off by an atom when it is passed through a prism? 3. What do the different colored lines correspond to? 4. Define the terms ground state and excited state and explain how an electron moves from ground to excited state and back again. 5. Explain how an atom can move between ground state and excited state. You can either be descriptive or draw/add a diagram to help with your explanation. 6. How can we view an element’s emission spectra? 7. Where does the color of light we initially see come from? Part 1: The Electromagnetic Spectrum Electromagnetic Spectrum VISIBLE Visible Light GREEN Part 2: Gas Discharge Tubes ELEMENT Hydrogen, H2 Helium, He Neon, Ne Mercury, Hg Argon, Ar COLOR EMISSION SPECTRA Carbon Dioxide, CO2 White Light Conclusion Questions: 1. Explain what is happening (in terms of the electrons) when you turn on the source and the gas discharge tubes light up. Be sure to use the terms excited state, ground state, absorb, and emit in your answer. 2. Explain what carbon dioxide’s spectra is unique. What is it showing? 3. What is the difference between the emission spectra of individual elements versus that of white light? 4. Why did each of the different elements have a different emission spectrum? Explain your answer. 5. How does this lab demonstrate the idea that emission spectra are like element “fingerprints”? 6. Look at the diagram of hydrogen’s emission spectrum below. We are only able to see 4 lines when we look at hydrogen’s spectrum, but there are many others. Why can’t we see the other lines?
